The present invention relates to a leveling instrumentxe2x80x94clamping device for fixing leveling instruments on the tripod platform of a tripod.
In order to fix geodetic instruments, e.g., leveling devices, leveling lasers, or the like, they are fixed on the tripod platform by means of a retaining bolt provided with every standard tripod. Depending on the embodiment of the tripod, either the leveling instrument, having a standard thread on its bottom, must be bolted onto a fixed bolt on the tripod, e.g., a crank tripod, or be bolted to the tripod platform by a bolt which can pass through a central recess in said tripod platform. Both types of fixing are awkward in their handling since the threaded bore into which the bolts must be screwed in are covered during mounting by the leveling instrument and face downward. Since mounting and separating are performed several times per day the process of screwing in is unpractical and time consuming.
Therefore, the present invention is based on the object of suggesting a possibility to mount a leveling instrument mentioned at the outset quicker than previously.
This object is attained according to the invention by a leveling instrumentxe2x80x94clamping device having the characteristics set out herein, including advantageous embodiments.
The leveling instrumentxe2x80x94clamping device according to the invention is provided with a device plate, which can be mounted to the bottom of the leveling instrument. This can occur via bolting, clamping, or any other suitable means of a secure connection. Basically, the device plate can be embodied round, circular, or angular as well. When screwing the leveling instrument in it can be rotated such that the threaded opening is visible. The top of the tripod platform is provided with at least one stop and one clamping device positioned at a distance from said stop by which the device plate can be clamped to the stop. The stop and the clamping device as well can be connected to the tripod platform either directly or via a plate. In a connection by means of a plate said plate can either be more or less imbedded into a recess of the tripod platform or can be positioned on top thereof. For instance, the clamping device can be either a device stretched by a spring or a clamping lever. Thus ensuring a quick fastening of the leveling instrument to the tripod and a correspondingly quick separability. Basically, the stop can be embodied differently according to the embodiment of the device plate. Correspondingly, the clamping by the clamping device can occur at the lateral circumference as well as on the top of the device plate.
According to one embodiment, the leveling instrumentxe2x80x94clamping device is provided with a base plate, which can be fastened on the tripod platform from below by means of a retaining bolt. The base plate is considerably more manageable than a leveling instrument and, therefore, it can be more easily connected to the retaining bolt before the leveling instrument is connected to the device plate. The base plate itself remains mounted to the tripod platform. It is also possible to imbed the base plate directly into the tripod platform and to connect it firmly.
For mounting the device plate to the leveling instrument said instrument is practically bolted into a threaded bore provided on the bottom of the leveling instrument. This can occur via a bolt or, preferably, via a threaded pin provided at the device plate.
According to a preferred embodiment the device plate is positioned in the open space between the stop and the clamping device and fixed to the circumference. This allows a simple construction of the device plate as well as the base plate, particularly when the stop is advantageously embodied by two pins protruding from the surface of the base plate.
In order to prevent that, in spite of the clamping of the device plate to the pins, the leveling instruments are able to shift upward, and the pins are preferably embodied tapering towards the base plate. Additionally, the device plate is correspondingly provided with a slope at its lateral circumference by which the device plate and the pins interlock.
According to another preferred embodiment the clamping device is embodied as a clamping lever pivotable around an axis perpendicular to the surface of the base plate so that the clamping of the device plate occurs in a plane parallel to the surface of the base plate. In order to achieve clamping between the clamping lever and the device plate the surfaces of the clamping lever and/or the device plate contacting one another are adjusted to one another. Preferably, the clamping lever is embodied as a lever.
Corresponding to the tapered pins, the clamping lever is also provided with a sloped area on its lateral circumference which corresponds to the slope on the circumference of the device plate and which interlocks with it during clamping.
By the leveling instrumentxe2x80x94clamping device according to the invention for mounting leveling instruments, such as levelers, theodolites, instruments for measuring the distance and the angle (total stations) or leveling lasers, to a tripod, a quick and secure fixing of said instruments is achieved in a simple manner.